1. Field of the Invention
The present invention relates generally to the color display of time series or space series information which may be discretely sampled or continuous in nature, in one or more dimensions, or in combination. More particularly, the present invention relates to a method of producing color displays of information wherein maximum differential perception by the interpreter of the display is assured.
2. Description of the Prior Art
Patents have been granted to methods which convert time or space series information whether called signals, waveforms, functions, graphs, or pictures into color outputs, the colors of which were assigned on the basis of some property of the series in question. One such patent, U.S. Pat. No. 3,961,306, teaches a method wherein the information is scaled into incremental ranges and each range is assigned a color corresponding to a sample value. The colors are assigned from a table that is constructed beforehand and which contains information relating to the densities of the various component displays required to make the assigned colors. The table is constructed by arbitrarily picking colors.
A shortcoming of the prior art is that the colors must be chosen beforehand, analyzed, and component densities chosen in order to create an assignment table. This task becomes arduous for a large number of ranges.
Another shortcoming of the prior art is that there is no teaching in any of the prior art patents of a method that assures maximal differential perception of the colors assigned to the output. For example, the usual system for assigning colors is spectrally; where, for example, large sample values are assigned colors near the violet end and small sample values are assigned colors near the red end, with intermediate values assigned in between. When a large number of sample values are displayed, the differences between colors assigned to closely spaced values become quite subtle and difficult, if not impossible, to discriminate.
A further shortcoming of the prior art is that there is no teaching of a method that takes into account color visual deficiencies among observers. There are color visual anomalies wherein the ability of an individual to perceive certain hues is either diminished or nonexistent. In methods based on arbitrary assignments of colors, certain hues that are clearly distinquished by normally sighted individuals are completely indistinquishable to those with a color vision deficiency. Such indistinquishability introduces ambiguity into the color display.